The invention relates to a sealing material for the underfilling of electronic and electrical components, which are sealed in an underfilling process for protection from environmental influences and to improve the resistance to fatigue of the solder connections of the components.
Sealing materials are known that consist of two-component epoxy resins, and that either must be mixed before processing or must be stored as a pre-mixture at -40.degree. C. At room temperature, they are available only for a few hours before they harden and become unusable. Disadvantages of this prior art include, on the one hand, the additional procedural step of the mixing of the two components before processing, and on the other hand the storage at low temperatures such as -40.degree. C. (see "Encapsulants used in Flip-Chip Packages," D. Suryanarayana, T. Y. Wu, J. A. Varcoe, IBM Microelectronics, IEEE Transact., Hybr., Manuf. Techn., Vol. 16, No. 8.858; 1993, and "Underfilling for Flip-Chip Mounting," M. Norris, Camelot Systems S. A. Conference proceedings "Adhesives in Electronics," Berlin 1994).
There is thus a need for sealing materials of this type that do not have to be mixed before processing and do not require storage at low temperatures.